Dietary iron intake is positively associated with hemoglobin concentration during infancy but not during the second year of life

Low iron stores in preconception nulliparous women; a two-center cross-sectional study in peri-urban Ghana

OBJECTIVES

The nutritional status of women affects pregnancy outcomes. Preconception care adequately prepares women for the demands of pregnancy. The aim of this study was to evaluate the prepregnancy iron status of nulliparous women in Ghana to provide empirical data to inform policy formulation.

METHODS

We recruited 336 nulliparous women of reproductive age from Denkyembour District and Ejura Municipal assemblies, respectively, in the Eastern and Ashanti regions of Ghana. Serum ferritin was estimated to assess the women's iron stores. Hemoglobin (Hb) variants and fecal occult blood were determined for participants using cellulose acetate electrophoresis and lateral flow chromatographic immunoassay, respectively. Logistic regression analysis was used to determine factors associated with depleted iron stores (ferritin < 15 ng/dL).

RESULTS

Whereas 41.5% of the women were anemic (Hb <11.5 g/dL), 34.5% were iron depleted (serum ferritin <15 g/mL; C-reactive protein <5 ng/dL). Also, 17.1% suffered from iron deficiency anemia (concomitant Hb <11.5 g/dL and serum ferritin <15 ng/dL). Serum ferritin significantly differed among the participants with anemia (P < 0.001). Multivariate regression analysis showed that age (<20 y: adjusted odds ratio [AOR], 13.916, P = 0.002; 20-30 y: AOR, 4.304, P = 0.023), moderate anemia (AOR, 3.045, P = 0.004), Ashanti region (AOR, 3.984, P = 0.002), and mean cell volume <80 fL (AOR, 2.546, P = 0.003) were significantly associated with increased odds of having depleted iron stores. However, body mass index, waist-to-hip ratio >0.85, educational status, or inherited Hb type were not significantly associated with depleted iron stores.

CONCLUSION

The high prevalence of depleted iron stores in nulliparous women is a severe public health problem that requires attention.

Efficacy of arginine depletion by ADI-PEG20 in an intracranial model of GBM

Glioblastoma multiforme (GBM) remains a cancer with a poor prognosis and few effective therapeutic options. Successful medical management of GBM is limited by the restricted access of drugs to the central nervous system (CNS) caused by the blood brain barrier (BBB). We previously showed that a subset of GBM are arginine auxotrophic because of transcriptional silencing of ASS1 and/or ASL and are sensitive to pegylated arginine deiminase (ADI-PEG20). However, it is unknown whether depletion of arginine in peripheral blood in vivo has therapeutic activity against intracranial disease. In the present work, we describe the efficacy of ADI-PEG20 in an intracranial model of human GBM in which tumour growth and regression are assessed in real time by measurement of luciferase activity. Animals bearing intracranial human GBM tumours of varying ASS status were treated with ADI-PEG20 alone or in combination with temozolomide and monitored for tumour growth and regression. Monotherapy ADI-PEG20 significantly reduces the intracranial growth of ASS1 negative GBM and extends survival of mice carrying ASS1 negative GBM without obvious toxicity. The combination of ADI-PEG20 with temozolomide (TMZ) demonstrates enhanced effects in both ASS1 negative and ASS1 positive backgrounds.Our data provide proof of principle for a therapeutic strategy for GBM using peripheral blood arginine depletion that does not require BBB passage of drug and is well tolerated. The ability of ADI-PEG20 to cytoreduce GBM and enhance the effects of temozolomide argues strongly for its early clinical evaluation in the treatment of GBM.

Iron intakes and status of 2-year-old children in the Cork BASELINE Birth Cohort Study

Young children are at risk of iron deficiency and subsequent anaemia, resulting in long-term consequences for cognitive, motor and behavioural development. This study aimed to describe the iron intakes, status and determinants of status in 2-year-old children. Data were collected prospectively in the mother-child Cork BASELINE Birth Cohort Study from 15 weeks' gestation throughout early childhood. At the 24-month assessment, serum ferritin, haemoglobin and mean corpuscular volume were measured, and food/nutrient intake data were collected using a 2-day weighed food diary. Iron status was assessed in 729 children (median [IQR] age: 2.1 [2.1, 2.2] years) and 468 completed a food diary. From the food diary, mean (SD) iron intakes were 6.8 (2.6) mg/day and 30% had intakes < UK Estimated Average Requirement (5.3 mg/day). Using WHO definitions, iron deficiency was observed in 4.6% (n = 31) and iron deficiency anaemia in five children (1.0%). Following an iron series workup, five more children were diagnosed with iron deficiency anaemia. Twenty-one per cent had ferritin concentrations <15 µg/L. Inadequate iron intakes (OR [95% CI]: 1.94 [1.09, 3.48]) and unmodified cows' milk intakes ≥ 400 mL/day (1.95 [1.07, 3.56]) increased the risk of low iron status. Iron-fortified formula consumption was associated with decreased risk (0.21 [0.11, 0.41] P < 0.05). In this, the largest study in toddlers in Europe, a lower prevalence of low iron status was observed than in previous reports. Compliance with dietary recommendations to limit cows' milk intakes in young children and consumption of iron-fortified products appears to have contributed to improved iron status at two years.

Impact of probiotic feeding during weaning on the serum lipid profile and plasma metabolome in infants

The gut microbiome interacts with the host in the metabolic response to diet, and early microbial aberrancies may be linked to the development of obesity and metabolic disorders later in life. Probiotics have been proposed to affect metabolic programming and blood lipid levels, although studies are lacking in infants. Here, we report on the lipid profile and global metabolic response following daily feeding of probiotics during weaning. A total of 179 healthy, term infants were randomised to daily intake of cereals with (n89) or without (n90) the addition ofLactobacillus paracaseissp.paracaseiF19 (LF19) 108colony-forming units per serving from 4 to 13 months of age. Weight, length and skinfold thickness were monitored. Venous blood was drawn at 5·5 and 13 months of age for analysis of the serum lipid profile. In a subsample, randomly selected from each group, GC-time-of-flight/MS was used to metabolically characterise plasma samples from thirty-seven infants. A combination of multi- and univariate analysis was applied to reveal differences related to LF19 treatment based on 228 putative metabolites, of which ninety-nine were identified or classified. We observed no effects of probiotic feeding on anthropometrics or the serum lipid profile. However, we detected significantly lower levels of palmitoleic acid (16 : 1) (P< 0·05) and significantly higher levels of putrescine (P< 0·01) in LF19-treated infants. Palmitoleic acid is a major MUFA strongly linked to visceral obesity, while putrescine is a polyamine with importance for gut integrity. Whether the observed differences will have long-term health consequences are being followed.

A micronutrient-fortified food enhances iron and selenium status of Zambian infants but has limited efficacy on zinc

Micronutrient-fortified, cereal-based infant foods are recommended for reducing multiple micronutrient deficiencies in low-income countries, but their nutritional quality is not always optimal. In a double-blind randomized trial, we compared the efficacy of a locally produced porridge based on maize, beans, bambaranuts, and groundnuts fortified with 19 (rich) or 9 (basal) micronutrients. Infants aged 6 mo from Lusaka, Zambia were randomized to receive the richly fortified (n = 373) or basal (n = 370) porridge daily for 12 mo along with routine vitamin A supplements. Baseline and final micronutrient status and inflammation (based on α-1-glycoprotein) were assessed using nonfasting blood samples. Baseline prevalence of anemia (39%) and zinc deficiency (51%) were a public health concern. There were overall treatment effects on hemoglobin (Hb) (P = 0.001), serum transferrin receptor (P < 0.001), serum ferritin (P < 0.001), and serum selenium (P = 0.009); biomarker responses for iron and zinc were modified by baseline concentrations, and for Hb and iron by socioeconomic status. At 18 mo, the adjusted odds of anemia, iron deficiency anemia (Hb <105 g/L and transferrin receptor > 11.0 mg/L), and iron deficiency were 0.37 (95% CI = 0.25, 0.55), 0.18 (0.09, 0.35), and 0.30 (0.18, 0.50) times those in the basal group, respectively. The rich level of fortification had no overall treatment effect on serum zinc (1.09; 0.66, 1.80) but improved serum zinc in children with lower Hb concentrations at baseline (P = 0.024). A locally produced cereal- and legume-based infant food richly fortified with micronutrients reduced anemia and improved iron and selenium status but may require reformulation to improve the biochemical zinc status of urban Zambian infants.

Long-term effects of iron and zinc supplementation during infancy on cognitive function at 9 y of age in northeast Thai children: a follow-up study

BACKGROUND

Iron and zinc are important micronutrients for child growth and development. One would expect that iron and zinc supplementation in infancy would affect long-term cognitive development and school achievement, but this has not been evaluated.

OBJECTIVE

We investigated the effect of iron or zinc supplementation or both during infancy on cognitive performance 8 y later.

DESIGN

A follow-up study was performed in 560 children aged 9 y or 92% of those who had participated in a randomized controlled trial involving 4 groups who received daily iron, zinc, iron plus zinc, or a placebo at 4-6 mo of age for 6 mo. Cognitive performance was assessed by using the Wechsler Intelligence Scale for Children-Third Edition (Thai version), the Raven's Colored Progressive Matrices (CPM), and school performance tests. General linear mixed models were used to assess long-term effects.

RESULTS

No significant differences in any of the outcomes at 9 y of age were observed at follow-up between the 4 groups. Mean intelligence quotients ranged across groups from 92.9 to 93.7 for full scale, 93.9-95.4 for verbal, and 93.1-94.0 for performance. The Raven's CPM score ranged from 21.4 to 22.4.

CONCLUSION

Supplementation with iron or zinc or both during infancy does not lead to long-term cognitive improvement in 9-y-old children. This trial was registered at clinicaltrials.gov as NCT00824304.

Iron, meat and health

This article is a summary of the publication "Iron and Health" by the Scientific Advisory Committee on Nutrition (SACN) to the U.K. Government (2010), which reviews the dietary intake of iron and the impact of different dietary patterns on the nutritional and health status of the U.K. population. It concludes that several uncertainties make it difficult to determine dose-response relationships or to confidently characterize the risks associated with iron deficiency or excess. The publication makes several recommendations concerning iron intakes from food, including meat, and from supplements, as well as recommendations for further research.

The beneficial effect of Mediterranean dietary patterns on dietary iron utilization in male adolescents aged 11-14 years

The effects of a diet based on Mediterranean patterns on iron bioavailability and iron status in adolescents were studied. The study was divided into two periods: basal period, in which 21 male adolescents consumed their habitual diet (basal diet); and nutritional intervention period, during which an experimental diet based on the Mediterranean model was consumed. Dietary iron utilization was studied by means of iron intake and iron output in faeces and urine, and iron status was analysed in fasting blood samples collected at the end of each period. No differences in total iron intake were found between diets, but consumption of the experimental diet increased iron absorption and retention compared with the basal diet. Biochemical parameters related to iron metabolism did not vary after the intervention period, although serum ferritin tended to increase. Therefore, a diet based on Mediterranean dietary patterns may improve dietary iron utilization during adolescence and may prevent iron deficiency.

Linear and ponderal growth trajectories in well-nourished, iron-sufficient infants are unimpaired by iron supplementation

Iron deficiency remains the most common nutritional deficiency worldwide and supplementation is recommended during periods of high risk, including infancy. However, questions have been raised about possible adverse effects of iron on growth in iron-sufficient (IS) infants and the advisability of across-the-board iron supplementation. This study examined whether short- or long-term growth was impaired in IS infants who received iron supplementation. From a longitudinal study of healthy, breast-fed, low- to middle-income Chilean infants randomly assigned to iron supplementation or usual nutrition at 6 or 12 mo, we retrospectively identified infants meeting criteria for iron sufficiency at the time of random assignment (n = 273). Using multilevel analysis, ponderal and linear growth were modeled before, during, and after iron supplementation up to 10 y in 3 comparisons: 1) iron supplementation compared with usual nutrition from 6 to 12 mo; 2) iron supplementation compared with usual nutrition from 12 to 18 mo; and 3) 15 mg/d of iron as drops compared with iron-fortified formula (12 mg/L). Growth trajectories did not differ during or after supplementation indicating no adverse effect of iron in any comparison. These results suggest that, at least in some environments, iron does not impair growth in IS infants.

Pro- and prebiotic supplementation induces a transient reduction in hemoglobin concentration in infants

OBJECTIVES

: Regarding safety, we investigated the effect of prenatal probiotic and 6 months of pro- and prebiotic supplementation of infants on their hematologic values at 6 months and 2 years and factors affecting these values.

PATIENTS AND METHODS

: In a prospective randomized controlled probiotic intervention trial in infants at high risk for allergy, we obtained blood samples consecutively from 98 infants at 6 months and from 658 children at 2 years to measure hematologic values. We collected fecal samples at 3 and 6 months to measure immunologic development by calprotectin, alpha-1-antitrypsin, tumor necrosis factor-alpha, and immunoglobulin A.

RESULTS

: At 6 months, infants in the probiotic group had significantly lower hemoglobin (Hb) values than did the placebo group, mean (SD): 119.8 g/L (6.3) versus 123.3 g/L (8.4), P = 0.025. Adjustment for factors that might affect Hb values (breast-feeding duration, solid-food introduction, and sex), revealed no need for adjustment. A significant negative correlation emerged between Hb values at 6 months and fecal calprotectin at age 3 months r = -0.301, P = 0.009, which was affected neither by breast-feeding, sex, nor study group. At 2 years, hematologic values in both groups became similar.

CONCLUSIONS

: Probiotics cause a gut mucosal inflammation with decreased Hb values during intervention, corrected after halting the supplementation.

Prevalence and predictors of iron deficiency in fully breastfed infants at 6 mo of age: comparison of data from 6 studies

BACKGROUND

Iron deficiency (ID) can occur among exclusively breastfed infants before 6 mo of age.

OBJECTIVE

The objective was to determine which subgroups of fully breastfed infants are at highest risk of ID.

DESIGN

We assessed the prevalence of ID (ferritin < 12 mug/L) and iron deficiency anemia (IDA; ferritin < 12 mug/L and hemoglobin < 105 g/L) and risk factors associated with ID and IDA at 6 mo among 404 fully breastfed infants with a birth weight >2500 g from 6 studies in Ghana, Honduras, Mexico, and Sweden. Infants with an elevated C-reactive protein concentration (8%) were excluded.

RESULTS

The percentages of infants with ID were 6% in Sweden, 17% in Mexico, 13-25% in Honduras, and 12-37% in Ghana. The percentages with IDA were 2% in Sweden, 4% in Mexico, 5-11% in Honduras, and 8-16% in Ghana. With data pooled, the key predictors of ID (20%) were male sex [adjusted odds ratio (AOR): 4.6; 95% CI: 2.5, 8.5] and birth weight 2500-2999 g (AOR: 2.4; 95% CI: 1.4, 4.3). The predictors of IDA (8%) were male sex (AOR: 7.6; 95% CI: 2.5, 23.0), birth weight of 2500-2999 g (AOR: 3.4; 1.5, 7.5), and weight gain above the median since birth (AOR: 3.4; 95% CI: 1.3, 8.6). The combination of birth weight 2500-2999 g or male sex had a sensitivity of 91% for identifying ID and of 97% for identifying IDA.

CONCLUSIONS

Among fully breastfed infants with a birth weight >2500 g, IDA is uncommon before 6 mo, but male infants and those with a birth weight of 2500-2999 g are at higher risk of ID and IDA.

Effects of mode of oral iron administration on serum ferritin and haemoglobin in infants

AIM

To investigate effects of iron-fortified foods (FFs) and medicinal iron drops (MD) on iron status in infants.

METHODS

Data from one MD and one FF study were compared. Infants were divided into groups depending on the predominant source and amount of dietary iron during 6-9 months of age: MD: Medicinal iron drops (1 mg/kg/day). FF: iron intake >1.3 mg/kg/day, predominantly from FF and no iron supplements. Low iron (LI) group: iron intake <1.3 mg/kg/day and no iron supplements.

RESULTS

Mean iron intake did not differ between MD (n = 30) and FF (n = 35) groups but was lower in the LI (n = 232) group. The FF group had significantly higher mean Hb at 9 months compared to the MD and LI groups (120 vs. 115 g/L and 120 vs. 116 g/L, respectively, p < or = 0.005). The MD group had significantly higher mean SF at 9 months compared to the FF and the LI groups (46 vs. 23 microg/L and 46 vs. 26 microg/L, respectively, p < 0.001).

CONCLUSIONS

Our results suggest that, in healthy, term, nonanaemic 6-9-month-old infants, iron given as medicinal iron drops is primarily deposited into iron stores while iron given as iron-fortified foods is primarily utilized for Hb synthesis.

Assessment of iron and zinc intake and related biochemical parameters in an adult Mediterranean population from southern Spain: influence of lifestyle factors

This study assessed factors influencing iron and zinc intake and associated biochemical parameters in an adult population from southern Spain to identify patterns of intake and groups at risk for deficiency. A cross-sectional survey was done in Andalusia (southern Spain) to study nutrient intakes in a random sample of 3421 subjects (1747 men, 1674 women, age between 25 and 60 years). Blood samples were obtained for biochemical assays in a random subsample of 354 subjects (170 men, 184 women). Food consumption was assessed by 48-h recall. In blood samples, we measured red blood cells, haemoglobin (Hb), haematocrit, total iron binding capacity (TIBC) and plasma concentration of Fe and Zn. Information about educational level, smoking habit, alcohol consumption and physical exercise was collected with a structured questionnaire. Intakes were below two thirds of the recommended dietary allowances (RDA) in 22.45% of the sample for Fe and in 56.45% for Zn. Iron deficiency [two or more abnormal values for plasma Fe, TIBC, transferrin saturation and mean cell volume (MCV)] was found in 12.7% of the sample, and iron-deficient anaemia (low values for Hb, MCV, mean cell Hb and mean corpuscular Hb concentration) was found in 2.1%. In smokers, plasma levels of Fe were higher, and MCV was lower than in nonsmokers. Plasma Zn concentrations were below the reference value in 17.8% of the persons. Age and body mass index correlated inversely with plasma Zn (P<.01). Gender, age, obesity, smoking, alcohol consumption and physical activity were associated with differences in nutrient intakes. Logistic regression analysis showed that female gender and older age were associated with the risk of low intakes of Fe and Zn.

Comparison of plasma ferritin concentration with the ratio of plasma transferrin receptor to ferritin in estimating body iron stores: results of 4 intervention trials

BACKGROUND

Efforts to develop global programs for the control of iron deficiency require simple, low-cost, and accurate indicators of iron status.

OBJECTIVE

We aimed to compare estimates of body iron (BI) stores, as calculated from either plasma ferritin concentration alone (BI-ferritin) or the ratio of plasma transferrin receptor (TfR) to ferritin (BI-TfR/ferritin).

DESIGN

Data were analyzed from 4 previously completed, randomized intervention trials that enrolled infants, schoolchildren, or pregnant women (total n = 1189, after excluding subjects with elevated C-reactive protein).

RESULTS

The correlation coefficients between BI-ferritin and BI-TfR/ferritin were >0.95 for all studies. The kappa index ranged from 0.5 to 1.0. All of the sensitivities of BI-ferritin for identifying persons with low iron stores (defined as BI-TfR/ferritin < 0 mg/kg body wt) were >0.90. All of the specificities were >0.90 except the study of pregnant women (specificity = 0.66). The effect sizes of iron intervention trials were significantly greater for change in iron reserves estimated by BI-TfR/ferritin than by BI-ferritin in 2 studies with larger effect sizes (1.11 compared with 1.00 and 1.56 compared with 1.44, respectively; P < 0.05) and 1 study with medium effect size (0.70 compared with 0.57; P < 0.05). However, there were no significant differences between estimates of these effect sizes for 1 study with a medium effect size and 1 study with a smaller effect size (0.78 compared with 0.83 and 0.37 compared with 0.35, respectively; P > 0.2).

CONCLUSION

Plasma ferritin concentration alone provides a good approximation of total BI reserves, as estimated by BI-TfR/ferritin, on the basis of high correlation, sensitivity, and specificity among nonpregnant persons with unelevated C-reactive protein.

Predictors of iron status in well-nourished 4-y-old children

BACKGROUND

Iron status in childhood is influenced by diet. Other factors affecting iron status at that age are unclear.

OBJECTIVES

The objectives of the study were to evaluate iron status in 4-y-old children, to track that status from infancy to childhood, and to examine the associations of iron status with dietary factors, growth, and heredity.

DESIGN

This study consisted of a longitudinal follow-up at age 4 y of children (n = 127) from the cohort of a study that began at age 6 mo. Blood samples and anthropometry were assessed in both children and their parents; food records were collected from children only.

RESULTS

Dietary intake was not significantly correlated with hemoglobin concentrations, whereas the consumption of meat products had a positive effect on serum ferritin concentrations and mean corpuscular volume in boys (P = 0.015 and 0.04, respectively). The prevalences of anemia and iron deficiency were low, affecting 2 (1.8%) and 3 (2.8%) children, respectively; no child had iron deficiency anemia. There was significant within-subject tracking of hemoglobin and mean corpuscular volume from age 6 mo to 4 y. The mother's but not the father's hemoglobin correlated with the child's hemoglobin over time.

CONCLUSIONS

Food choices had little effect on iron status. Hemoglobin concentrations and mean corpuscular volume were tracked from infancy to childhood. In healthy, well-nourished children with a low prevalence of iron deficiency, the mother's hemoglobin was significantly associated with that of her child, but the underlying mechanism is unclear.

Growth and micronutrient status in children receiving a fortified complementary food

Linear growth retardation and anemia are the most prevalent nutritional problems in the world; effective interventions are urgently needed. We evaluated Ecuador's National Food Nutrition Program (PANN 2000) that included a micronutrient-fortified complementary food (FCF), Mi Papilla, in poor periurban and rural communities of Ecuador. The program is preventive and targeted to all infants and young children living in poor communities and receiving government health services. We compared dietary intake, micronutrient status, and growth over 11 mo in a cohort of children from the catchment areas of the PANN 2000 with same-age control children in nearby communities eligible to enter the program 1 y later. PANN 2000 children enrolled in the program when they were age 9-14 mo and were age 20-25 mo at the final survey. They consumed significantly more energy, protein, fat, iron, zinc, vitamin A, and calcium than control children because of their FCF consumption. Anemia, 76% in both groups at baseline, fell to 27% in PANN 2000 children but only to 44% in control children (P < 0.001). The odds of being anemic were 58% lower for PANN 2000 children (P = 0.003). The effects on linear growth and weight were limited to children who were older when the program began (12-14 mo) and were significant for weight (interaction with age, 0.38 kg; P = 0.029) and positive but not significant for length (0.66 cm; P = 0.08). An FCF, including ferrous sulfate, delivered through public health services, is highly effective in improving weight and hemoglobin and reducing anemia.

[Dietary iron and iron deficiency anemia among adolescent girls from Benin]

BACKGROUND

Iron deficiency anemia affects a large number of women in developing countries, especially during childbearing years. Few studies determined the association between estimated absorbable iron intakes and iron deficiency.

METHODS

The association between dietary iron intake and iron status was studied in 100 adolescent girls aged 14-16 years from Benin. Fifty adolescents were boarding at the school, while 50 lived at home. Biochemical indices of iron status included: hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin concentration, serum iron, total iron-binding capacity and % transferrin saturation. Dietary intakes were obtained by two 24-hour recalls and absorbable iron intakes were estimated using Monsen's model. The probability approach was used to estimate inadequacy in iron intake.

RESULTS

While 73% of adolescents met the recommendations for dietary iron intake, only 27% had estimated absorbable iron intake above the average requirement for absorbed iron. Non-heme iron represented 97.2% of the total iron intake. Forty three percent of subjects were anemic (hemoglobin<120 g/l). Iron deficiency defined by a four-model index based on > or =2 abnormal values in the four independent indicators of iron status used (serum iron, total iron-binding capacity, mean corpuscular volume, mean corpuscular hemoglobin concentration) was present in 14% of the subjects, while 13% had iron deficiency anaemia (hemoglobin<120 g/l+four-model index). Using a multiple regression analysis, total absorbable iron intakes (including iron supplements) were highly and positively associated with hemoglobin and hematocrit concentrations (P=0.000001 and P=0.00007 respectively).

CONCLUSION

In this group of adolescents, total absorbable iron intakes were related to iron deficiency. Efforts should be made to increase the heme iron content of the diet and the bioavailability of non-heme iron by promoting affordable local foods rich in iron and promoters of iron absorption (Vitamin C and meat, poultry and fish factor).

Iron status of inner-city African-American infants

The iron status of African-American infants continues to be subject to debate. We characterized the iron status of 198 9-month-old inner-city infants (94% fed iron-fortified formula) using a comprehensive panel of measures and assessing lead and inflammation markers. The proportion with iron deficiency was calculated based on three approaches (> or = 2 abnormal iron measures with or without anemia for MCV model--NHANES II, ferritin model--NHANES III, or Sweden/Honduras study) and a promising new measure-body iron, calculated from ferritin and transferrin receptor (TfR). There were no sex differences for any iron measure. Hb < 110 g/l was observed in 25%; Hb < or = 105 g/l in 10.1%. Free erythrocyte protoporphyrin (FEP) values were elevated without elevated lead concentrations or an inflammatory response: mean FEP = 86.6 microg/dl red blood cells [75.5 micromol/mol heme]; 52.3% were > 80 microg/dl (1.42 micromol/l), almost half of which were accompanied by a second abnormal iron measure. The estimated prevalence of iron deficiency was 14.4, 5.3, and 2.5% for the MCV model, ferritin model, and Sweden/Honduras cutoffs, respectively, and 4.1% for body iron < 0 mg/kg. Regulation of iron storage is immature at < 1 year of age, making estimates of iron deficiency that depend on ferritin, including body iron, suspect in this age period. Thus, the "true" prevalence of iron deficiency could not be established with confidence due to major differences in the results, depending on the guidelines used. Functional indicators of poor iron status in young infants are urgently needed.

Associations of iron status with dietary and other factors in 6-year-old children

OBJECTIVE

To investigate the associations of iron status at 6 years of age with dietary and other factors.

DESIGN

In a cross-sectional study, children's dietary intakes (3-day weighed food record) were recorded, body size was measured and blood samples were taken near their sixth birthday.

SUBJECTS

A sample of 188 children, from two previous studies (cohorts 1 and 2), was contacted, and 139 (74%) agreed to participate.

RESULTS

Multiple regression analyses with dietary and other factors showed that meat and fish consumption, multivitamin/mineral supplement intake (both positively) and cow's milk product consumption (negatively) were associated with log serum ferritin (SF) (adjusted R (2)=0.125; P=0.028; n=129), and juices and residence (rural>urban) with haemoglobin (Hb) (adjusted R (2)=0.085; P=0.034; n=127). Of 21 multivitamin/mineral consumers, none had depleted iron stores compared to 21 iron-depleted of 108 non-consumers (P=0.024). Children living in rural areas (<10,000 inhabitants) (n=33) had higher mean corpuscular volume (MCV) (83.3+/-2.3 fl) than those living in urban areas (>10,000 inhabitants) (82.1+/-3.2 fl; n=103) (P=0.048). Multiple regression analyses with dietary and other factors and growth showed in cohort 1 that residence (rural>urban), weight gain 0-1years (negatively), and meat and fish intake (positively) were associated with Hb (adjusted R (2)=0.323; P=0.030; n=51), meat and fish (positively) with both log SF (adjusted R (2)=0.069; P=0.035; n=52) and MCV (adjusted R (2)=0.064; P=0.035; n=52), and in cohort 2 cow's milk product consumption (negatively) was associated with log SF (adjusted R (2)=0.119; P=0.017; n=41) and residence (rural>urban) with MCV (adjusted R (2)=0.102; P=0.025; n=41).

CONCLUSIONS

Consumption of meat and fish and possibly also juices, as well as multivitamin/mineral intake might affect iron status in 6-year-old children positively, whereas cow's milk product consumption might affect iron status negatively. Slower growth in the first year of life and rural residence are positively related to iron status of 6-year-olds.

Risk of infant anemia is associated with exclusive breast-feeding and maternal anemia in a Mexican cohort

The WHO recommends exclusive breast-feeding (EBF) for the first 6 mo of life to decrease the burden of infectious disease. However, some are concerned about the effect of EBF >6 mo on iron status of children in developing countries in which anemia is prevalent. This study examines the risk of anemia in relation to the duration of EBF and maternal anemia in a birth cohort studied between March 1998 and April 2003. All infant birth weights were >or=2.2 kg. All mothers received home-based peer counseling to promote EBF. Infant feeding data were collected weekly. Nurses measured hemoglobin (Hb) values every 3 mo. Hb was measured in 183 infants at 9 mo of age. Anemia at 9 mo was defined as a Hb value <100 g/L. EBF was defined by WHO criteria and ranged in duration from 0 to 31 wk. At 9 mo, Hb (mean +/- SEM) was 114 +/- 0.9 g/L; 23 children (12.5%) had Hb levels <100 g/L. EBF >6 mo, but not EBF 4-6 mo, was associated with increased risk of infant anemia compared with EBF <4 mo (odds ratio=18.4, 95% CI=1.9, 174.0). Maternal anemia was independently (P=0.03) associated with a 3-fold increased risk of infant anemia. These associations were not explained by confounding with other maternal or infant factors. By linear regression, a lower infant Hb at 9 mo was associated with increased EBF duration among mothers who had a history of anemia (beta=-0.07, P=0.003), but not among mothers with no history of anemia. Infants who are exclusively breast-fed for >6 mo in developing countries may be at increased risk of anemia, especially among mothers with a poor iron status; greater attention to this issue is warranted.

[Variations in serum ferritin and erythrocyte index in the first eight weeks of life in term newborn infants]

OBJECTIVE

To describe changes in erythrocyte index during the first 8 weeks of life in neonates in relation to their iron store.

MATERIAL AND METHODS

We performed a longitudinal study of a group of healthy term newborn infants, in whom we evaluated erythrocyte index and serum ferritin (SF) values at birth and at weeks 4 and 8 of age. Depending on the comparison made in SF values between birth and 2 months, the infants were divided into two groups: group I (without variation in SF) and group II (with a decrease in SF).

RESULTS

A total of 110 neonates were included, with 46 neonates in group I and 64 in group II. No differences in demographic or hematologic data were found, including neonates with anemia or a decrease in hemoglobin values (5.2 vs. 5.5 g/dL). SF decreased to lower values in group II than in group I (215 vs. 194 microg/L, p < 0.001), with a greater number of neonates with low iron stores at 2 months of age (0.15 vs. 0.37, p < 0.01; RR 2.464, 95 % CI: 1.162-5.227).

CONCLUSIONS

In healthy term newborn infants, erythrocyte index at birth showed no relation with iron store. SF values at 2 months of age depended on SF concentrations at birth. Decreased hemoglobin and SF values are part of physiological adaptation in the first few months of life.